Reversing device for toothed gearing



F. LJUNGSTRUM, l. BROBERG AND E. O. ERIKSSON.

REVERSING DEVICE FOR TOOTHED GEARING.

APPLICATION FILED MAY 28. 1919.

IIIIIIIIIIII/IIII/A Patented Aug. 23, 1921.-

4 SHEETS-SHEET I.

IIIIIIIIIIIIIIIIII F. LJUNGSTROM, I BRUBERG AND E. O. ERIKSSON. REVERSING DEVICE FOR TOOTHED GEARING.

APPLICATION F!LED MAYZS, I9I9- 1,388,351, Patented Aug. 23, 1921.

4 SHEETS-SHEEY 3.

Izweztboza EL] 1012/ S1511! am I. .Br 0 e1 1221: i/lisson/ F.LJUNGSIBOM, I. BROBERG AND E. 0. ERIKSSON.

REVERSING DEVICE FOR TOOTHED (iEARING.

APILICAHON HLEU MAY28. IQ'IQ.

1,888,351. t t dAug- 23,1921.

4 SHEEfS-SHEEf 4.

81 E I I A; l

UNITED STATES PATENT OFFICE.

rmamux uunss'rnom. or LIDINGON-IBREVIK, ISIDOR BROBERG, or TALLHYDDAN,SKAIRSATRA, AND ERIK o'r'ro ERIKSSON, or ORMBUNKEN, mmvrx, mnmeon,SWEDEN, ASSIGNORS T0 AKTIEBOLAGET LJ'UNGSTROMS AINGTURBIN, or s'rocx-HOLE, SWEDEN, A CORPORATION.

Specification of Letters Patent.

Patented Aug. 23, 1921.

Application filed Kay 28, 1919. Serial No. 800,380.

T 0 all whom it may concern.

Be it known that' we, FREDRIK. LJUNG- sTRoM, residing atLidingon-Brevlk, Sweden, ISIDOR BROBERG, residing at Tallhyddan,Skarsatra, Sweden, and ERIK O'r'ro EnrxssoN, residing at ,Ormbunken,Brevilr, Lidingon, Sweden, subjects of the King of Sweden, have inventednew and useful Improvements in Reversing Devices for Toothed Gearing, ofwhich the following is a specification.

In toothed gearing provided with a reversing device and more especiallyin vehicle gearing said reversing device has been generally so arrangedas to have the reversing take place by an axial displacement of anadditional toothed wheel, such displacement being effected manually.With this arrangement it has been often necessary to use a frictioncoupling between the various parts of the gearing, in order tofacilitate the engagement of the toothed wheels'with each other, withoutsubjecting them to breakage when coupling their teeth in incorrectrelative position. 7

When employing large gearings transmitting considerable amounts ofpower, the above mentioned design of gearing cannot be advantageouslyused, and other means for effecting the reversal had to be devised, inorder to prevent the gearing from being de-, stroyed. V

In accordance with the present invention, this object is attained by soconnect ng the reversing device with the gearing or with the startingmeans for the driving fluid for the gearing that the reversing devicecannot be operated as long as any one of the gear wheels is rotating, oras long as the driving same being movable in a radial direction andadapted to be thrown in and out of mesh between the driving and thedriven gear wheels. By the present invention the axial extension of thegearing is considerably reduced' as compared with constructionsemploying wheels which are axially displaced, and as the additionaltoothed wheel requires only a small space to permit the same to bethrown in and outof engagement, the whole gearingwill be appreciablyreduced in size. The invention also includes an arran ement forobtaining such positions of the i la wheels to be thrown in engagementwith each other, that a tooth of one wheel is, at the moment ofeffecting the couplin always situated opposite the tooth space 0 theother wheel. If the wheels are moved toward 'each other and their teethare not in a posipelled to rotate under friction on the other wheeluntil tooth and tooth space are situated opposite each other. Thisresult can be advantageously obtained by usingspiral cut' wheels, as theengagement of such wheels will always occur at the point of tangencyofthe circles, so that a rotary movement of one wheel does notbring aboutany chan e in the distance between the centers of the wheels.

An embodiment of the invention is shown in the accompanying drawings inwhich Figure 1 is a diagrammatic view.

Fig. 2 is a similar view with certain added details shown in section.

Fig. 3 is a sectional view taken on a-a of Fig. 2.

Fig. 4 shows a detail of the mechanism shown in Fig. 2.

Fig. 5 is a detail sectional view of the controlling valve and itscylinder taken on line 5-5 of Fig. 7.

Fig. 6 is a similar view taken on line 66 of Fig. 7

' Fig. 7 is an axial section of the valve taken on line 77 of Figs. 5, 6and 8.

Fig. 8 is a horizontal sectional view taken on line 88 of Fig; 7.

Fig. 9 is a view similar to Fig. 7 but showthe line ing the valvedepressed to permit fluid from 7 its interior to pass to the means forascertaining whether the wheels are revolving, said section being takenon line 9-9 of Fig. 10.

ig. 10 is a horizontal sectional view taken on line 10-10 of Fig. 9.

Fig. 11 is an axial sectional view taken on line 11-11 of Figs. 12 and13 and showing the valve further depressed for admitting fluid to thecylinder which controls the unlocking and locking of the reversing gearshifting means.

Figs. 12 and 13 are horizontal sections taken on lines 12-12 and 1313 ofFig. 11. Fig. 14 is an axial section taken on line 1414 of Figs. 15 and16 and showing the valve turned in a clock-wise direction to admit fluidto the cylinder which controls valve and the cylinders.

Referring particularly to Fig. 1, 1 denotes a driving wheel and 2 adriven toothed wheel. The wheel 1 is always supposed to rotate in thesame direction, whereas the wheel 2 can rotate in either direction, thatis to say forward, when it is driven directly from the wheel 1, or inthe opposite direction when driven from the wheel 1 through the mediumof the intermediate wheel 3. 4, 5 and 6 designate the shafts of thewheels 1, 2 and 3 respectively.

Thus the wheels 2 and 3 are to be displaced when changing from forwardto rearward movement or vice versa, such displacement being effected bymeans of the following mechanism.

In the position shown in the drawing, wheel 2 is rotating backward. Whena reversal is to take place, oil is introduced into the cylinder 7 underthe piston 8 through the lower inlet 9, the said introduction of oilbeing effected upon the stopping of all wheels by means of anarrangement shown in detail in Fig. 2. The piston 8 is then raisedwithin the cylinder and thereby moves the stud 10 to the point 11, theshaft 13 being simultaneously rotated by means of the crank 12. The cam14 and the crank 15 are. rigid with the shaft 13. When the latter isbeing rotated, the cam 14 raises the frame-work 16 together with theshaft 5 and the toothed wheel 2. On account of the shape of the cam thisdoes not, however, take place before the crank 12 has passed theintermediate position 17. The toothed wheel 3 is eccentrically journaledin the disk 18 and when the shaft 13 is turned, this disk will berotated by means of the crank 15 and the rod 19 during the movement10-17, the toothed wheel 3 being thereby moved out of mesh with thetoothed wheels 1 and 2. During the latter part of the reversing motion17 11, the crank 15 is turned still more, so that the pin 20 isdisplaced to the point 21, the pin 22 on the rod 19 to the point 23, theshaft 6 to the point 24, and this causes the wheel 3 to assume theposition indicated by the dotand dash lines in the drawing. During theperiod of this latter movement, the cam 14 is turned so that the framework 16 is raised to a position, wherein the axis of the shaft 5 issituated at a -;point 25. In this position of the shaft 5 the toothedwheels 1 and 2 are in direct engagement with each other and the toothedwheel 3 is out of mesh.

In case the teeth of the wheels 1 and 2 have been brought in suchrelative positions, when the tooth of the one wheel is not situatedopposite the tooth space of the other cient angle of movement. Thearrangement will be described more in detail with reference to Fig. 2. vI

Now if it is desired to effect a backward motion of the wheel 1, thepiston 8 is lowered, the wheel 2 being thereby first thrown out of mesh,whereupon the Wheel 3 is thrown in enga ement. If free running of thegearing is esired, the piston 8 is actuated so that the stud 10 willstop at 17 In this position neither the wheel 2 nor the wheel 3 is inengagement with the wheel 1.

In Fig. 2'the same embodiment is illustrated as in Fig. 1, the same,however, being shown in detail. Fig. 2 particularly illustrates thearrangement preventing reversing before all of the wheels contained inthe gearing are standing still.

The reference characters common to both figures designate similar partsof the construction. In this case all of the oil cylinders are operatedby means of a starting arm 30 which may be lowered as well as rotated.

The starting arm is pivoted in the lug 33 of the piston slide valve 32by means of a pin 31. The piston slide valve 32 may thus be rotated andbrought up .or down in the oil cvlinder 34 by means of the arm 30. Thewalls of the piston slide valve and the cylinder are rovided withpassage ways, communicating with the various oil cylinders.

Bv means of different movements of the starting arm 30, oil isintroduced into the As indicated in the introduction offthisvspecification, the reversing device has to be so connected with thegearing or with the starting means forthe driving fluid, thatthereversing device cannot be brought into operation as long as any one ofthe wheels of the gearing is rotating.

In the embodiment illustrated, the arm 30 cannot be actuated before thewheels of the gearing or any one of them has been stopped. This may beeffected in the following manner.

56 denotes the starting lever for the driving fluid, for instance thestarting lever of the steam supply of a locomotive. As long as thislever 56 occupies such a position that the driving fluid is acting thearm 30 is locked and vice versa, when the arm 30 is in its operativeposition, starting of the driving fluid cannot take place. This isaccomplished by means of two stopping bolts 57 g which in the normalpositions of the handles, as shown in the drawing, are pushed intorecesses in the operating lever at 58 and 59 respectively by means of aspring disposed between the bolts.

In the operating lever, the recess 58 is situated in a spherical surface60 and this recess is of such a depth that the left hand bolt is lockedin saidrecess in all positions of the lever 56 but the normal one, thatis to say the position in which both stopping bolts are in the recesses.The same arrangement is provided for at 59 in the arm 56, and thus onlyone of these two arms at one time may be turned from its normalposition. Thus the oil operating lever 30 for the reversal of the gearwheels is locked on all occasions, when the driving fluid is acting. Thearm 30 mav be operated only when the starting handle 56 for the drivingfluid occupies the position shown in Fig. 2, that is to say when thedriving fluid is not acting and vice versa, the starting handle 56 maybe displaced from the position shown in the draw- .ing and the motorstarted only when thearm 30 occupies its normal position, shown in thedrawing.

. Now, if reversing is to take place, for instance, from forward tobackward, that is to say, if the wheel 3 is to be thrown in mesh, suchoperation will be effected inthe following manner.

To begin with the starting handle 56 for the. driving fluid has to be,brought into the positionshown in the drawing so as to cut ofl.

such fluid.

Then the arm 30 is turned around its pivot 31 by pressing down thehandle. This arm 30 may be turned around the longitudinal axis of thepiston slide 32 in a clockwise as well as in a counter-clockwisedirection; turning in the one direction brings about the reversal fromforward to backward, in the other direction and from'backward toforward. The arm cannot, however, be turned, before the gear wheels arestanding still as it may happen that the gear wheels continue to rotateafter the cut-off of the driving fluid,

particularly inlvehicles the motion of which is continued owing toinertia, such as locomotives.

To prevent the turning of the arm 30 before the gear wheels have come torest, the following arrangement has been provided.

Then the arm 30 is turned about its pivot 31, the piston slide 32 ispressed down, oil being thereby admitted froma pressure-oil receptacleinto two oil cylinders 73, the pistons 71 0f which actuate thesemi-circular friction wheels 37 and 38 or other similar members so asto press them against frictional tracks 74 on the wheels 1 and 2. Thesedisks are moved against the wheels 1 and 2 in an axial direction asshown, and

for this purpose they are beveled. If one I or both of the wheels 1 and2 is or are rotating at this time, the corresponding or both wheels 37and 38 will be turned so that the studs 39 and 40 are displaceddownward. A pin 41 will also be moved downward, and

this will cause a lever 42 to be turned so as to push up a rod 43. Thisrod 43 will in such case be introduced into a hole 44 in the startinglever 30, the latter being thereby locked so that it cannot be furtheroperated or turned. Suitable means such as a spring 70, Fig. 3,insertedbetween the piston 71 and the fixed casing 72 tends to move thesystem 3643 back into the position shown in the drawing, therebyovercoming all friction.- As mentioned, the arm 30 may be turned only incase all of the gear wheels are standing. still. Assuming that this willA at last be the case, then when the arm 30 is pressed down on anothertrial, the rod 43 will not be lifted, and thus the arm 30 may be turnedso as to effect thevreversal.

The arm having been turned somewhat so as to move the boss 35 of the arm30 past the boss 35, the arm 30 maybe pressed down farther until thepiston 32 reaches the bot-.

tom of the cylinder 34." On this second movement downward, whether thearm has been turned to the' right or the left, oil is admitted under'apiston-like end 45 of the the cylinder 7, the said cylinder 7 effectingthe coupling and uncoupling of the toothed wheel 3, ashereinbefqredescribed with reference to Fig. 1.

When the piston slide valve 32 is again lifted, oil will be dischargedfrom the space under .the piston 45 which is brought back into its lowerextreme position by means of the spring 75. A beveled toothed segment 49is fixed to the shaft 13 and when the shaft is turned, the segment 49drivesa beveled gear 51 fixed to the lower end of a spindle 50. Thespindle 51 is so roportioned rela tively to the segment 49 t at thespindle 50 can never turn more than half a revolution, in order that thelocking device 4747- or 47"47 shall fit in the two extremev positions. Awheel 52 fixed to the spindle 46 is driven by the wheel 48, the spindle46 being provided with a square-head adapted to be engaged by a crankhandle (not shown),

The two recesses 47 and 47* may be relaced by a single one. 47 denotes arecess ibr free running.

The upper part of the spindle 46 coacts with the arm which is rovidedwith a ball-shaped end- 76 that pro ects into a space provided betweentwo guiding flanges 7 7 on V the spindle 46. By this arrangement the arm30 cannot be brought back into itsnormal position before the locking ofwheel 48 by means of the locking disk 48, the latter holding the spindle46 in its raised position on all occasions when the reversing device isnot locked for forward, rearward or free running. The device not beinglocked,

the spindle and consequently its point of connection with the arm 30 areraised, and

the latter cannot then be brought back into its normal position. Thusthe device in question prevents the driver of the locomotive fromadmitting steam before the re-' versal has been completed. v

The spindle 46 which is threaded at 53 is also provided with a nut 53having a pointer 54 indicating the position held by the gearing, thesaid pointer 54 moving over a scale 54. e

As it is of the utmost importance that the wheels 1 and 3 are brought insuch a position relatively to each other, when being thrown in mesh,that the teeth thereof fit exactly, the following arrangement has beenprovided which always places the wheels in the position required.

A piston 61 moves within an oil cylinder" '55 which also-receivespressure-oil through the medium of the piston slide valve 32, when'thelatter is moved to the position in which oil is admitted to the cylinder7. The

said piston 61 is. provided with two levers 26, the points of whichcoact with locking rings 62 on the wheels 1 and 3, which looking ringsare provided with the same number of teeth as the gear wheels 1 and 3.The

piston 61 is provided with a cross pin 63 projecting through slots 64 inthe cylinder 55. A pressure spring 65 has one of its ends abuttingagainst the ends of the cross pin 63 and its opposite end abuttingagainst the bottom of the casing 66. The said spring tends to hold thepiston 61 in its upper extreme position against the pressure of oilwhich is introduced into the space 67 within the casing 66.

The levers 26 are provided with cam surfaces 68 coacting with the edgeof the opening 69 in such manner that the levers 26 are extreme positionwhereby the two wheels 1 and 3, provided they are not in mesh, areturned to such positions that coupling of the wheels can take place.

In a similar manner the wheels 2 and 3 are brought into engagement withone another, the wheel 3 bein turned by the lever 26 while a proachingthe wheel 2. In case a tooth of t e wheel 3 strikes a tooth of the wheel2, the wheel 3 can be continually moved by the lever 26 during the timethat the wheels are incontact until a tooth thereof is brought intoengagement with a tooth space of the wheel 2, provided the toothedwheels are spirally cut. In such case the wheels will always come incontact with each other about in the same manner as two cylinders, viz.,at a point coinciding .with a straight line connecting the centers ofthe wheels. If on the contrary this device is employed in spur gears, itmay happen that two teeth will meet before reaching the said line. Insuch case the wheels cannot be turned until a tooth is brought intoengagement with a tooth space, the turning being prevented by the teethmeeting each other, and therefore the wheels are compelled to moveapart, whereupon a new attempt must be made for setting the wheels.

In Figs. 5-7 the oil-starting device is shown in detail.

F igs.'5 to 6 inclusive illustrate the difi'erent positions of the valvewhich controls the admission and exhaust of the actuating fluid whichoperates the various pistons.

In Figs. 5, 6, 7 and 8. the valve is shown in inoperative position. Atthis time it may be stated that the conduit 81 leads from the valvechamber 34 to the cylinder 73; the conduit 83 leads from chamber 34 tothe cylinder 45; the conduit 89 extends from the chamber 34 to thecylinder 55; and the conduits 85 and 86 lead from the chamber 34 to thetop and bottom of the cylinder 7. Fluid is admitted to the interior ofthe valve through a passage 121 and the fluid is emitted through anexhaust passage 91.

The valve body 32 is provided at its upper portion with radial ports 87and 88 and a semicircular slot 80.. The lower portion of the valve isprovided with a circumferentially extending recess 90 and a radial port84. An axially extending recess 108 is also provided in the valve bodyand communicates with the recess 90. In the position shown in Fig. 7,the exhaust 91 is connected through the recess 90 in the slide valve 32with the conduits 81, 83, 85 and 86, and the conduit 89 is connectedthrough the recess 108 with the exhaust 91. By depression of the arm 30investigation is first made whether the different wheels of the gearingare standing still. This position is illustrated in Fig. 9. In suchosition the slide valve 32 is depressed su ciently into the c linder sothat the port 80 in the wall of t e valve connects the conduit 81 withthe interior of the slide valve which by means of the oil conduit 121 isin communication with the oil supply. If it is'found that the wheels ofthe gearing are standing still, the arm 30 and the slide valve areturned to a certain extent and then depressed to the position shown inFig. 12. In this position the oil conduit 83 leading to the piston 45 isconnected with the pressure oil within the slide valve 32 by means ofthe port 80, the locking device of the gearing thereby being released.On further turning of the arm 30, the port 84 is brought-into alinementwith one of the conduits 85 or 86 and oil is admitted to the cylinder 7at one side of its piston thus adjusting the wheels to forward running.At the same time the port 88 in the wall of the valve connects theinterior of the latter with the oil conduit 89 thus setting theadjusting device 6126 in operation.

For afi'ecting backward running, the arm 30 and the slide valve areturned from the position shown in Fig. 8 in anopposite direction, oilthen being supplied to the cylinder 7 at the opposite side of its pistonfor adjusting the wheels to backward runnin and to'the device 6126through the port 8%. The slide valve 32 maintains always the connectionbetween the outlet 21 and the side of the piston in the cylinder 7 notbeing conthe oil supply and connected with the exhaust 91 in a coursecontrary to that followed when being connected with the oil supply. a

The interior of the cylinder 32 containing pressure oil is connected bymeans of the exhaust 91 with the oil supply reservoir so by LettersPatent of the United States is 1. In toothed gearings, a reversingdevice comprising a member in gear with any one of the rotating parts ofthe gearing, motion transmitting members actuated by said member andlocking members adapted to lock the reversing device and to be set inoperation by said motion transmitting members.

2. A reversing device as set forth in claim 1 and further characterizedby a rotary arm (30) adapted to be operated by pressure oil and to actupon a piston (32) serving as a valve for said oil.

3. A reversing device as set forth in claim 1 and further characterizedby the slide valve (32) being so arranged as to cause the oil to besupplied to cylinders actuating pistons which are connected with rotarymembers adapted to .bear against friction tracks connected with any oneof the gear wheels,

4. A reversing device as set forth in claim 1 and further characterizedby a swingable frame (16) supporting one (2) of the wheels of thegearing, and a rotary disk (18) eccentrically supporting an intermediatewheel (3), the frame and the disk being operated by means of the slidevalve (32) by the aid of pressure oil.

5. A reversing device as set forth in claim 1 and further characterizedby the frame (16) and the disk (18) being connected with a shaft (13) insuch manner that, upon the rotation of the shaft (13) in one direction,the intermediate wheel (3) is first disengaged and the wheel (2)thereupon brought whereas, upon rotation of the shaft (13) in oppositedirection the wheel (2) is first disengaged from the wheel (1) and theintermediate wheel (3) then M coupled to both wheels (1) and (2).

6. A reversing device as set forth in claim 1 and further characterizedby the shaft 13) beingconnected with a piston movable in a c linder towhich pressure oil is supplied at either side of the piston according tothe direction of rotation of the arm (30).

7. A reversing device as set forth in claim land further characterizedby the frame (16) being operated by a cam (14) secured to the shaft(13), whereas the disk (18) is operated by a crank ,(12) attached tosaid shaft and by a rod (19) pivotally connected with said crank andsaid disk.

. 8. A reversing device as set forth in claim 1 and furthercharacterized by each of the reversing device and the starting device ofthe drivlng medium being provided with a locking mechanism, thereversing device acting upon the locking mechanism of the startingdevice and the latter upon the reversing device.

, 9. A reversing device as set forth in claim 1 and furthercharacterized by the arm (30) and a starting handle (56) being connectedin such manner that only one of them is capable of assuming a positionother than the normal one, the normal position of the handle (56) beingthat one in which the driving medium is shut off. 7

10. A reversing device as set forth in claim 1 and further characterizedby the arm (30) and the handle (56) being locked in normal position by acommon stop which, upon the movement of one of said members out of thenormal position, is moved so as to lock the other member.

11. A reversing device as set forth in claim 1 and further characterizedby the stop being retained, upon the movement of one of the members outof the normal position, in the position in which the other member islocked, so long as the latter assumes a position other than the normalone, for instance by the two members being provided with suitablebearing surfaces for the sto 1 2. A reversing device as set forth inclaim 1 I and further characterized by a member which, on coupling thegear wheels, is adapted to move the same to a position in which theteeth of one wheel are situated just opposite the spaces between theteeth of the other wheel.

13. A reversing device as set forth in claim 1 and further characterizedby the device for adjusting the gear wheels to correct positionconsisting of a piston (61) movable in a cylinder (55) and adapted to beactuated by pressure oil in the position of the slide valve (32) inwhich the reversing device is operated.

14. A reversing device as set forth in claim 1 and further characterizedby the gear wheels to be coupled being provided with toothed rims (62)cooperating with levers (26) connected with the piston (61).

15. A. reversing device as set forth in cla1m 1 and furthercharacterized by the levers (26) being so arranged as not to cooperatewith the toothed rims in one end position of the piston (61).

16. A reversing device as set forth in claim 1 and further characterizedby the levers (26) being provided With sliding surfaces (68) adapted, onthe movement of the piston (61) to one end position, to bear against theedge of an opening (69) in the cylinder so as to move the levers (26)out of engagement with the toothed rims.

17. In toothed gearing, a reversing gear adapted to mesh with aplurality of gears for reversing the movement of one of said gears,means for moving said reversing gear into engagement with said pluralityof gears, and means for preventing movement of the latter means untilone of said gears has ceased to rotate. 18. In toothedgearing, areversing gear adapted to mesh with a plurality of gears for reversingthe movement of one of said gears, means for moving said reversing gearinto engagement with said plurality of gears, and means for alining atooth of said reversing gear wth a tooth space of one of said pluralityof gears.

19. A gearing of the kind defined by! claim 18 having means forpreventing movement of the reversing gear moving means until one of saidgears has ceased to rotate.

20. In gearing mechanism, in combination a driving gear, a driven gear,and a reversing gear adapted to be thrown into mesh with the driving anddriven gear when the direction of motion of the driven gear is to bereversed, means for ascertaining Whether one of said driving or drivengears is rotating, means for bringing the teeth of one of said drivingor driven gears into correct position to be engaged by the other one ofsaid driving or driven gears, and means for moving said reversing gearinto engagement with said driving and driven gears.

In witness whereof we have hereunto set our hands in the presence of twowitnesses.

FREDRIK LJUNGsTRoM. ISIDOR BROBERG. ERIK OTTO ERIKSSON.

Witnesses GRETA PRICU, Er sn MAHMAU.

